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Lead-free halide perovskites have attracted widespread research interest due to their excellent optoelectronic properties and environmental friendliness. As one of the bismuth iodide compounds, Cs3Bi2I9 perovskite has been extensively explored in the field of photovoltaic devices and radiation detectors due to their non-toxic lead-free components and excellent stability. In this work, we successfully grow large-sized Cs3Bi2I9 single crystals (SC) with (l 00) and (00 l) crystal exposure facets by inverse temperature crystallization method. Under 525 nm light illumination with the intensity 15 mW cm−2 and 7 V bias, the (l 00) Cs3Bi2I9 SC shows 2 times higher photocurrent, 3.6 times higher responsivity, and 2.8 times higher detectivity than the (00 l) Cs3Bi2I9 SC, respectively. Superior response time in the scale of millisecond is obtained in both (l 00) and (00 l) Cs3Bi2I9 SCs. Based on the first-principle calculation, the (l 00) SC possesses a higher charge distribution density and a wider dispersion distribution than (00 l) SC, suggesting that more electrons in the (l 00) SC can be excited in a wider range. The tighter arrangement of Cs+ and [BiI6]− octahedra in the (l 00) SC than (00 l) SC leads to the anisotropic photoelectric performance in (l 00) and (00 l) Cs3Bi2I9 SCs. Our results provide a strategy for the oriental growth of Cs3Bi2I9 SCs and the design of anisotropic optoelectronic devices with excellent performance. [ABSTRACT FROM AUTHOR]

New data favor the view previously substantiated by geological, geochemical and isotopic data that the orebodies of the Belogorskoe deposit are the Triassic erosion products of the laterite weathering crust after gabbroids, which were metamorphosed and partially regenerated in the Late Cretaceous–Paleogene. The source for the formation of the Belogorskoe deposit was shown to be the products of exogenic destruction of rocks, the isotopic and geochemical characteristics of which are close to those of Cambrian gabbroids of the Vladimiro-Aleksandrovsky massif (southern part of the Okrainsko-Sergeevsky terrane). It has been found that the Belogorskoe deposit consists of rocks and ores, the primary (magmatic) REE distribution in which was variably modified as a result of interaction between sediments (protoliths) and seawater (presumably during the Late Jurassic–Early Cretaceous accretion), as well as between their metamorphosed analogues and hydrothermal solutions (in the Late Cretaceous–Paleogene). The influence of gabbroids (as a source of material) on the chemical and mineral composition of the Belogorskoe deposit agrees with the data reported in a paper on the enrichment of orebodies in such elements as Fe and Mn characteristic of ultramafic rocks and the presence of Au–Ag–Pd–Pt, Ni–Co, and Bi mineralization in them. The orebodies of the Belogorskoe deposit contain accessory minerals and mineral varieties that are rare in nature and poorly studied. They include an unusually Th-rich variety of zircon, baddeleyite, gudmundite, a large group of bismuth compounds, including Bi2Te, (Ag,Pb)BiS2, as well as coloradoite, lafossaite, sanbornite, perovskite, and the compound InPO4. There is also a large group of rare and unusual noble metal compounds: copper gold, platinum gold, jonassonite, disordered solid solutions of Cu, Ag and Au (Au-based), Pt–Pd, Pt–Ag intermetallides, and other rare minerals and mineral varieties. [ABSTRACT FROM AUTHOR]

This research employs the COMSOL Multiphysics software (COMSOL 6.2) to conduct rigorous simulations and assess the performance of a thermoelectric module (TEM) meticulously crafted with alumina (Al2O3), copper (Cu), and Bi2Te2.70Se0.30 thermoelectric (TE) materials. The specific focus is on evaluating diverse aspects of the Bi2Te2.70Se0.30 thermoelectric generator (TEG). The TEM design incorporates Bi2Te2.70Se0.30 for TE legs of the p- and n-type positioned among the Cu layers, Cu as the electrical conductor, and Al2O3 serving as an electrical insulator between the top and bottom layers. A thorough investigation is conducted into critical parameters within the TEM, which include arc length, electric potential, normalized current density, temperature gradient, total heat source, and total net energy rate. The geometric configuration of the square-shaped Bi2Te2.70Se0.30 TEM, measuring 1 mm × 1 mm × 2.5 mm with a 0.25 mm Al2O3 thickness and a 0.125 mm Cu thickness, is scrutinized. This study delves into the transport phenomena of TE devices, exploring the impacts of the Seebeck coefficient (S), thermal conductivity (k), and electrical conductivity (σ) on the temperature differential across the leg geometry. Modeling studies underscore the substantial influence of S = ±2.41 × 10−3 V/K, revealing improved thermal conductivity and decreased electrical conductivity at lower temperatures. The findings highlight the Bi2Te2.70Se0.30 TEM's high potential for TEG applications, offering valuable insights into design and performance considerations crucial for advancing TE technology. [ABSTRACT FROM AUTHOR]

BiOI and (3 wt%)GO/BiOI visible-light-driven photocatalysts were obtained by a one-pot solvothermal method and successfully applied to the degradation of single and binary dye solutions of rhodamine B (RhB) and methylene blue (MB) and H2 production using very low-power sources. The GO/BiOI with hierarchical flower morphologies exhibited the highest activity, achieving RhB and MB photodegradation percentages (%Xdye) of 100% and 80%, respectively, in 240 min employing a simple 19 W white LED array. Furthermore, GO/BiOI dosage and RhB initial concentration play an essential role in dye degradation, and scavenger assays confirmed that holes and superoxides are the main species causing RhB oxidation. TOC analysis determined an efficiency of 70%, and after three uses, the GO/BiOI attained a %XRhB of 84%. The H2 evolution was performed under 2 W UV light, yielding 323.25 μmol/h·g of H2 for BiOI, and the addition of GO nanosheets increased the photoactivity of GO/BiOI up to 63% (509.61 μmol/ h·g). The catalytic activity of GO/BiOI is superior to values reported in the literature considering nominal power consumption (kWh) vs. efficiency of RhB degradation or H2 production. [ABSTRACT FROM AUTHOR]

Non-isocyanate polyurethane synthesis by non-Sn catalysis is an essential challenge toward green polyurethane synthesis. Bismuth compounds are attractive candidates due to their low cost, low toxicity, and availability to urethane chemistry. This work applied various Bi catalysts to the self-polycondensation of a bishydroxyurethane monomer and found BiCl3 to be an excellent catalyst through optimization. The catalytic activity and price of BiCl3 are comparable to those of Bu2SnO, while its toxicity is significantly low. BiCl3 is, therefore, a promising alternative to Sn-based catalysts in non-isocyanate polyurethane synthesis. [ABSTRACT FROM AUTHOR]

The magnetic, electronic, and structural properties of the cubic phase of lead-doped alloys of praseodymium bismuth compounds with the generic formula PrPbxBi1-x (x = 0, 0.25, 0.50, 0.75, and 1.0) have been reported in this paper by employing the formalism of density functional theory (DFT). For the analysis of physical properties, we have executed the full-potential linearized augmented plane wave plus local orbit (FPLAPW+lo) technique, while the exchange-correlation potentials in the Kohn-Sham equation (KSE) are implemented within the generalized gradient approximation (GGA) extended by the Perdew-Burke-Ernzerhof (PBE) correction. The structural parameters, lattice constants, volume, bulk modulus, pressure derivatives, and energy have been computed with the Wein2k code by fitting total energy through Murnaghan's equation of state. The structural stability of the compounds has been reported from the spin-polarized calculations. The electronic energy bands and total and partial densities of states of the compounds have been calculated in both majority and minority spins, depicting them as metallic. The similar spectrum intensities of the Pr(5d+4f) and (Pb +Bi)2p states account for the majority of the contribution to the density of states near the Fermi energy level. The spin magnetic moments computed for the supercell of the doped compounds have indicated that they are magnetic materials. From the comparison of spin magnetic moments in the PrBi compound, we noticed an improvement in the magnetic moments after doping lead into the PrBi compound. [ABSTRACT FROM AUTHOR]

Purpose: The work focuses on preparing and characterising BNT-based ceramics via a solidstate method. To investigate the phase, microstructure, and physical and electrical properties of BNT-based ceramics. Design/methodology/approach: Lead-free piezoelectric bismuth sodium titanate -- bismuth potassium titanate -- stronsium zirconate (BNT-BKT-SZ) ceramics were fabricated by the solidstate reaction method. The effect of sintering temperature with soaking times of 2, 4, and 6 h at 1150°C on structural, microstructure, density, porosity, and electrical properties was examined. The phase formation of the ceramics was examined using X-ray diffraction (XRD). Scanning electron microscopy (SEM) (JEOL JSM5910LV) was employed to investigate ceramic microstructure. The bulk density and mechanical properties of the sample were measured using Archimedes' method, respectively. The electrical properties of ceramics, such as dielectrics, ferroelectrics, and piezoelectrics, were investigated. Findings: XRD showed all samples had a single perovskite structure and no secondary phase. All sintered samples at different temperatures have a coexisting phase boundary between the rhombohedral phase and the tetragonal phase. The sintered ceramic at 1150°C with a soaking time of 4 h shows a maximum density of 5.89 g/cm3. In addition, the temperature at which the sintering process is carried out substantially impacts the electrical characteristics. Dielectric and electric field-induced strain (Smax) properties that sintered at 1150°C with a soaking time of 4 h exhibited the highest values of 4.489 and 0.39% (d33* of 650 pm/V), respectively. Research limitations/implications: The impact of the coercive field on the electrical breakdown characteristics of ceramics should be investigated further in the course of research that has to be carried out. Practical implications: The characterisation confirmed the effects of sintering temperature on the physical, phase, microstructure, and electrical properties of BNT-based ceramics. Originality/value: Such research demonstrates a suitable sintering temperature for producing BNT-BKT-SZ. The mechanical and electrical properties of a material are dependent on its sintering parameters. The ceramic system is suitable for piezoelectric and/or energy storage applications. [ABSTRACT FROM AUTHOR]

The thermal transport properties of Bi2Te2Se topological insulators show a range of complex features. Large bulk resistivities coexisting with prominent Shubnikov–de Haas quantum oscillations and proximity to metallic states mark this p-band system as an unconventional topological quantum material. Here, using the density functional plus dynamical mean-field theory method, we show how localization–delocalization transition underpins the T-dependence of thermoelectric responses from room down to low temperatures. We present the implications of our many-particle analysis to resistivity, Seebeck coefficient, thermal conductivity, and Lorenz number and propose that related broadband systems close to electronic transitions could be of use in thermoelectrics. [ABSTRACT FROM AUTHOR]

Whereas indications of radical reactivity in bismuth compounds can be traced back to the 19th century, the preparation and characterization of both transient and persistent bismuth‐radical species has only been established in recent decades. These advancements led to the emergence of the field of bismuth radical chemistry, mirroring the progress seen for other main‐group elements. The seminal and fundamental studies in this area have ultimately paved the way for the development of catalytic methodologies involving bismuth‐radical intermediates, a promising approach that remains largely untapped in the broad landscape of synthetic organic chemistry. In this review, we delve into the milestones that eventually led to the present state‐of‐the‐art in the field of radical bismuth chemistry. Our focus aims at outlining the intrinsic discoveries in fundamental inorganic/organometallic chemistry and contextualizing their practical applications in organic synthesis and catalysis. [ABSTRACT FROM AUTHOR]

Bismuth layered compound with the composition SrBi1.5La0.5Nb2O9 has been prepared using conventional solid-state reaction method. Crystallographic planes have been identified using X-ray diffraction studies. The dielectric studies have been done as a function of frequency and temperature. Low temperature dielectric measurement shows phase transition in which peak dielectric constant shifts from 260K to 280K with the increase in frequency from 1 kHz to 1 MHz. Room temperature dielectric constant has been found to be nearly frequency independent for this composition making it a potential candidate for the capacitor applications. The prepared ceramic was modelled using the Vogel – Fulcher relationship. [ABSTRACT FROM AUTHOR]

Bismuth compounds are considered relatively non-toxic, with their low solubility in aqueous solutions (e.g., biological fluids) being the major contributing factor to this property. Bismuth derivatives are widely used for the treatment of peptic ulcers, functional dyspepsia, and chronic gastritis. Moreover, the properties of bismuth compounds have also been extensively explored in two main fields of action: antimicrobial and anticancer. Despite the clinical interest of bismuth-based drugs, several side effects have also been reported. In fact, excessive acute ingestion of bismuth, or abuse for an extended period of time, can lead to toxicity. However, evidence has demonstrated that the discontinuation of these compounds usually reverses their toxic effects. Notwithstanding, the continuously growing use of bismuth products suggests that it is indeed part of our environment and our daily lives, which urges a more in-depth review and investigation into its possible undesired activities. Therefore, this review aims to update the pharmaco-toxicological properties of bismuth compounds. A special focus will be given to in vitro, in vivo, and clinical studies exploring their toxicity. [ABSTRACT FROM AUTHOR]

The interlayer interactions in multilayer systems with a non-magnetic semimetallic interlayer are great of interest. The magnetic and structural properties of the DyxCo1-x/Bi/Py systems (17 < x < 26 at.%) have been studied. The temperature dependences of magnetization in the range 4.2–300 K were measured for the first time. The influence of the bismuth interlayer thickness on the exchange interaction between the DyCo and Py layers was found as well as the critical value of its thickness. The obtained atypical value of the period of exchange bias oscillations was explained by the formation of bismuth compounds with dysprosium–pnictogenides at bismuth thicknesses below the critical value. The interface was investigated by spectral ellipsometry in the range 2–5 eV. The information on the structure of the surface obtained by atomic force microscopy was used to create a multilayer model for fitting experimental ellipsometric data. Analysis of the optical properties showed that pnictogenide Dy3Bi2 is formed at the interface, which affects the general magnetic state of the samples studied. [ABSTRACT FROM AUTHOR]

BiOI and (3 wt%)GO/BiOI visible-light-driven photocatalysts were obtained by a one-pot solvothermal method and successfully applied to the degradation of single and binary dye solutions of rhodamine B (RhB) and methylene blue (MB) and H2 production using very low-power sources. The GO/BiOI with hierarchical flower morphologies exhibited the highest activity, achieving RhB and MB photodegradation percentages (%Xdye) of 100% and 80%, respectively, in 240 min employing a simple 19 W white LED array. Furthermore, GO/BiOI dosage and RhB initial concentration play an essential role in dye degradation, and scavenger assays confirmed that holes and superoxides are the main species causing RhB oxidation. TOC analysis determined an efficiency of 70%, and after three uses, the GO/BiOI attained a %XRhB of 84%. The H2 evolution was performed under 2 W UV light, yielding 323.25 μmol/h∙g of H2 for BiOI, and the addition of GO nanosheets increased the photoactivity of GO/BiOI up to 63% (509.61 μmol/h∙g). The catalytic activity of GO/BiOI is superior to values reported in the literature considering nominal power consumption (kWh) vs. efficiency of RhB degradation or H2 production.

Bi(Fe0.5Mn0.5)O3 is an Mn substituted Bismuth ferrite ferroelectric synthesized following mixed oxide process method of solid-state reaction technique after calcined at 800 °C for 8 h. XRD study approves the development of an orthorhombic single-phase new crystal structure. Electrical characterization of the compound is done by an impedance analyzer. The dielectric and impedance study of the material is investigated in a wide span of frequency (102–106 Hz) and temperature (30–500 °C). The parent compound bismuth ferrite has a higher transition temperature (∼830 °C) which markedly decreases to 470 °C on substitution of Mn is substituted at the B site. Impedance study of the compound exhibits non-Debye type relaxation process. With the rising temperature, the relaxation frequency shifts toward the high frequency side. From the plots of complex impedance, negative temperature coefficient of resistance (NTCR) behavior like semiconductor is noticed. The conductivity is mainly contributed by the grain in the material. [ABSTRACT FROM AUTHOR]

Background: Until now, there have been no randomized controlled trials directly evaluating the efficacy of high-dose ilaprazole-amoxicillin dual therapy (HT) in comparison to other standard treatments for H. pylori (Helicobacter pylori) infection. This study aimed to compare the effectiveness and safety of HT with bismuth quadruple therapy (BQT) as an initial treatment for H. pylori. Methods: This single-center, prospective, randomized clinical controlled trial recruited 225 consecutive patients. They were assigned to either HT group (ilaprazole, 10 mg, twice daily; amoxicillin 1,000 mg, three times daily) or BQT group (compound bismuth aluminate granules, 2.6 g, three times daily; ilaprazole, 5 mg, twice daily; amoxicillin, 1,000 mg, twice daily; clarithromycin, 500 mg, twice daily) for 14 days. The 13C-urea breath test assessed eradication success 4 weeks after treatment. The primary outcome focused on the eradication rate, with secondary outcomes including safety and compliance. Results: From February 2023 to March 2023, 228 subjects were screened, and 225 were randomized. The HT and BQT groups showed eradication rates of 76.3% and 61.3% (p = 0.015) both by intention-to-treat (ITT) analysis and per-protocol (PP) analysis. HT was associated with fewer adverse events than BQT (27.2% vs. 81.8%, p = 0.002). The most commonly reported adverse events was bitter taste of mouth (3.5% vs. 60.4%, p < 0.001). There was no significant difference in compliance between the two groups (89.5% vs. 92.8%, p = 0.264). Conclusion: The 14-day HT treatment demonstrates better efficacy in H. pylori eradication treatment and improved safety and compliance compared to BQT. The results provide supporting evidence for 14-day HT can be potentially considered as a first-line regimen for empirical treatment. [ABSTRACT FROM AUTHOR]

Objective • To investigate the clinical impact of dietary intervention in combination with bismuth potassium citrate in the management of chronic atrophic gastritis (CAG) caused by Helicobacter pylori. Methods • From April 2019 to October 2022, 160 patients with newly identified Helicobacter pylori-related CAG were treated at our facility. They were split into two groups at random: the bismuth potassium citrate medication group (n = 80) and the diet intervention + bismuth potassium citrate experimental groups (n = 80). The bismuth potassium citrate treatment group was given bismuth potassium citrate capsule treatment only, and the diet intervention + bismuth potassium citrate treatment group was given diet intervention based on bismuth potassium citrate capsule. The diet intervention score, symptom score, and pathological score of the two groups were observed at baseline and after treatment, and the relationship between dietary intervention and symptoms and pathology of Helicobacter pylori-related CAG was analyzed. Results • During the baseline period, there was no discernible difference in the diet intervention score, symptom score, or pathology score between the two groups (P > .05); after the diet intervention combination treatment, the diet intervention score, diet intervention + bismuth potassium citrate experimental groups symptom score, and pathology score were considerably lower than those in the bismuth potassium citrate treated group (P < .05). Conclusions • Dietary intervention combined with bismuth potassium citrate exhibited more effective treatment than bismuth potassium citrate-only treatment in Helicobacter pylori-related CAG, which hinted us proper diet has a positive impact on improving the therapeutic efficacy of bismuth potassium citrate. [ABSTRACT FROM AUTHOR]

Developing a high-performance piezocatalyst that directly transforms mechanical energy into hydrogen is highly desirable in the field of new energy. Herein, the Aurivillius-layered Bi2WO6 (BWO) nanoplates are prepared through a hydrothermal reaction at a moderate temperature of 160 °C, and exhibit strong piezoelectric properties, enabling them to catalyze water splitting through ultrasonic-induced piezocatalysis effect. The hydrogen evolution reaction (HER) and H2O2 generation efficiencies are measured to be 0.43 and 0.36 mmol g−1 h−1, respectively. To further boost piezocatalytic performance, cobalt oxide nanoparticles are intentionally photo-deposited onto these nanoplates as cocatalyst. This configuration results in a significantly boosted HER performance with an efficiency of 3.59 mmol g−1 h−1, which is 2.8 times higher than that of pristine nanoplates and demonstrates strong competitiveness compared to other reported piezocatalysts. The cobalt oxide cocatalyst plays a crucial role in facilitating efficient charge separation and migration, increasing the charge concentration, and ultimately enhancing piezocatalytic HER activity. Overall, this work highlights the potential of Aurivillius-layered bismuth oxide compounds as efficient piezocatalysts and provides valuable insights for designing high-performance piezocatalysts in the field of new energy. [ABSTRACT FROM AUTHOR]

Reprogrammable soft matter brings flexibility to soft robots so that they can display various motions, which is flourishing in soft robotics. However, the reprogramming of photoresponsive materials used in soft robots is time-consuming using existing methods. In this study, we promote a strategy for rapid reprogramming via switchable photothermal conversion efficiency (PCE). The liquid crystalline elastomers doped with semiconductor bismuth compounds (Bi-LCE) used in this work exhibited large photothermal actuation with over 35% shrinkage in 5 s at high PCE state, which demonstrated little deformation at low PCE state. Furthermore, the material was capable of being reprogrammed up to 10 times, with only 20 min required for one PCE reversible switch. Based on this switchable PCE effect, the same Bi-LCE film displayed various shape changes through different programmable pattern. Additionally, a reprogrammable hollow tube made of PCE reprogrammable materials could tune the diameter, cross-section configuration, and surface morphology, which was crucial for microfluidics field. Reprogrammable materials provide endless possibilities for reusability and sustainability in robotics. [ABSTRACT FROM AUTHOR]

Dynamic covalent chemistry (DCvC) is a powerful and widely applied tool in modern synthetic chemistry, which is based on the reversible cleavage and formation of covalent bonds. One of the inherent strengths of this approach is the perspective to reversibly generate in an operationally simple approach novel structural motifs that are difficult or impossible to access with more traditional methods and require multiple bond cleaving and bond forming steps. To date, these fundamentally important synthetic and conceptual challenges in the context of DCvC have predominantly been tackled by exploiting compounds of lighter p‐block elements, even though heavier p‐block elements show low bond dissociation energies and appear to be ideally suited for this approach. Here we show that a dinuclear organometallic bismuth compound, containing BiMe2 groups that are connected by a thioxanthene linker, readily undergoes selective and reversible cleavage of its Bi−C bonds upon exposure to external stimuli. The exploitation of DCvC in the field of organometallic heavy p‐block chemistry grants access to unprecedented macrocyclic and barrel‐type oligonuclear compounds. [ABSTRACT FROM AUTHOR]

Bismuth oxyhalides (BiOX) including BiOCl, BiOBr, and BiOI, were well synthesized using solvothermal technique and then used in the aqueous phase photooxidation of glycerol as a catalyst. The as-synthesized BiOBr could achieve the highest glycerol transformation of around 85.6% in 8 h under ultraviolet light (UV) irradiation among as-synthesized BiOXs. Moreover, the BiOBr/TiO2 heterojunction was also prepared through an ethylene glycol-assisted solvothermal process. This new BiOBr/TiO2 heterostructure exhibited excellent photocatalytic activity (97.4%) for the oxidation of glycerol compared with pure BiOBr (74%) under ultraviolet light irradiation at 6 h. This obtained behavior was confirmed by more produced OH• radicals of BiOBr/TiO2. [ABSTRACT FROM AUTHOR]

Bismuth-based drugs have been used primarily to treat ulcers caused by Helicobacter pylori and other gastrointestinal ailments. Combined with antibiotics, these drugs also possess synergistic activity, making them ideal for multiple therapy regimens and overcoming bacterial resistance. Compounds based on bismuth have a low cost, are safe for human use, and some of them are also effective against tumoral cells, leishmaniasis, fungi, and viruses. However, these compounds have limited bioavailability in physiological environments. As a result, there is a growing interest in developing new bismuth compounds and approaches to overcome this challenge. Considering the beneficial properties of bismuth and the importance of discovering new drugs, this review focused on the last decade's updates involving bismuth compounds, especially those with potent activity and low toxicity, desirable characteristics for developing new drugs. In addition, bismuth-based compounds with dual activity were also highlighted, as well as their modes of action and structure–activity relationship, among other relevant discoveries. In this way, we hope this review provides a fertile ground for rationalizing new bismuth-based drugs. [ABSTRACT FROM AUTHOR]

Lewis acidic bismuth compounds have found catalytic applications in the reduction of unsaturated bonds. In this work, we present the inferences from the mechanistic studies on the catalytic reduction of ketones and phosphine oxides using the organobismuth dication [NMe2C6H4Bi(L)3][Al{OC(CF3)3}4]2 in the presence of silanes as reducing agents. Experiments and computations converge to a Si−H activation pathway in the reduction process. [ABSTRACT FROM AUTHOR]

Silver bismuth sulfide (AgBi2S3) belongs to the I–V–VI group of semiconducting materials and is a non-toxic, earth capacious compound. It has an energy gap of 1.2 eV, which is very close to the exemplary energy gap of 1.39 eV for solar cell absorbers. It also has a high absorption coefficient of 105 cm−1 at 600 nm. This work reports the chemical deposition of a nanostructured thin film of ternary compound silver bismuth sulfide (AgBi2S3) on a mesoporous layer of titanium dioxide (TiO2) deposited by a spin coating method. The synthesized layer of TiO2/AgBi2S3 was characterized by techniques such as XRD, UV–visible spectroscopy, surface morphology, energy dispersive x-ray composition analysis, and cross-section. Nanoparticles of the ternary metal chalcogenide AgBi2S3 with a diameter of about 150–200 nm were synthesized chemically, and this layer, with a thickness of about 15 µm, was deposited on the FTO glass substrate. The absorbance of TiO2/AgBi2S3 thin film increased over the entire visible and IR regions of the spectrum. TiO2's optical energy gap was reduced from 3.07 eV to 1.7 eV after sensitization with AgBi2S3 nanoparticles. The results of characterization confirm the deposition of a very thin layer of TiO2/AgBi2S3, which will be further explored for photovoltaic applications. [ABSTRACT FROM AUTHOR]

Bismuth compounds are considered relatively non-toxic, with their low solubility in aqueous solutions (e.g., biological fluids) being the major contributing factor to this property. Bismuth derivatives are widely used for the treatment of peptic ulcers, functional dyspepsia, and chronic gastritis. Moreover, the properties of bismuth compounds have also been extensively explored in two main fields of action: antimicrobial and anticancer. Despite the clinical interest of bismuth-based drugs, several side effects have also been reported. In fact, excessive acute ingestion of bismuth, or abuse for an extended period of time, can lead to toxicity. However, evidence has demonstrated that the discontinuation of these compounds usually reverses their toxic effects. Notwithstanding, the continuously growing use of bismuth products suggests that it is indeed part of our environment and our daily lives, which urges a more in-depth review and investigation into its possible undesired activities. Therefore, this review aims to update the pharmaco-toxicological properties of bismuth compounds. A special focus will be given to in vitro, in vivo, and clinical studies exploring their toxicity.

This review article provides an overview of the properties and methods for synthesis of BiSI and Bi13S18I2 semiconductor compounds in the form of thin films, powders and crystals, as well as their application in photovoltaic and photoelectrochemical devices. Over the past decade, the results of extensive and versatile research on the structure, properties, functionality and potential applications of bismuth-containing semiconductor materials have accumulated. Bismuth halides and chalcohalides are a developing class of materials that have a small band gap, high chemical stability, effective absorbing properties when absorbing light radiation, which causes the registration of high quantum efficiency values and the possibility of their use in photoelectrochemical processes and photovoltaic solid-state elements. This review presents the results of recent developments and basic approaches aimed at obtaining various multicomponent compounds based on bismuth and improving photoelectrochemical properties. Various structures which demonstrate the importance of thin films based on bismuth compounds are also described. The key problems related to the synthesis and development of these materials is presented. This review will provide a deeper understanding and determine the preferred direction for the synthesis of bismuth-containing thin films for energy and environmental applications.

Key challenges in modern synthetic chemistry include the design of reliable, selective, and more sustainable synthetic methods, as well as the development of promising candidates for new materials. Molecular bismuth compounds offer valuable opportunities as they show an intriguing spectrum of properties that is yet to be fully exploited: a soft character, a rich coordination chemistry, the availability of a broad variety of oxidation states (at least +V to −I) and formal charges (at least +3 to −3) at the Bi atoms, and reversible switching between multiple oxidation states. All this is paired with the status of a non‐precious (semi−)metal of good availability and a tendency towards low toxicity. Recent findings show that some of these properties only come into reach, or can be substantially optimized, when charged compounds are specifically addressed. In this review, essential contributions to the synthesis, analyses, and utilization of ionic bismuth compounds are highlighted. [ABSTRACT FROM AUTHOR]

Lead‐free heavy halogenido metalates are currently under intense investigation, as they show similarly promising semiconducting properties as their famous but toxic lead relatives. A major interest in this regard is the understanding and control of optical properties with the goal of designing highly efficient photoconducting materials. Here, we present two isostructural iodido pentelates (Hpyz)3E2I9 ⋅ 2H2O (pyz=pyrazine; E=Sb, Bi). Both compounds are stable up to 100 °C. We observe an inverted order of band gap sizes, 1.91 eV and 1.98 eV for the antimony and bismuth compound, respectively, compared to similar pairs of compounds. We use DFT calculations to confirm that this surprising finding can be traced back to the presence of charge transfer excitations in both compounds. [ABSTRACT FROM AUTHOR]

Simple and cost-effective procedures for the direct integration of ferroelectric perovskite oxides into Ni structures are necessary to realize related multifunctional metallic microelectromechanical systems, such as dual-source energy harvesters. This is especially difficult in the case of lead-containing morphotropic phase boundary materials for high piezoelectric response because the two components are thermodynamically incompatible and the formation of NiOx or perovskite oxide reduction takes place depending on the processing conditions. We show here that low-temperature solution processing is an effective means to kinetically limit nickel oxidation, capable of providing BiFeO3–PbTiO3 films on Ni plates at only 500 °C. Bulk-like ferroelectric properties and a distinctive magnetoelectric response were attained. This perovskite system, not explored before on Ni, has a much larger switchable polarization than the widely studied Pb(Zr,Ti)O3, and it is shown here to present an excellent downscaling behavior of ferroelectric properties until the verge of the nanoscale. [ABSTRACT FROM AUTHOR]

Although discovered 40 years ago, Helicobacter pylori infection is still raising diagnostic and therapeutic problems today. The infection is currently managed based on statements in several guidelines, but implementing them in practice is a long process. Increasing antibiotic resistance and weak compliance of the patients limit the efficacy of eradication regimens, leaving much room for improvement. Third-generation proton pump inhibitors have added little to the results of the first two generations. Potassium-competitive acid blockers have a stronger and longer inhibitory action of acid secretion, increasing the intragastric pH. They obtained superior results in eradication when compared to proton pump inhibitors. Instead of innovative antibiotics, derivatives of existing antimicrobials were developed; some new fluoroquinolones and nitazoxanide seem promising in practice, but they are not recommended by the guidelines. Carbonic anhydrase inhibitors have both anti-secretory and bactericidal effects, and some researchers are expecting their revival in the treatment of infection. Capsules containing components of the eradication regimens have obtained excellent results, but are of limited availability. Probiotics, if containing bacteria with anti-Helicobacter pylori activity, may be useful, increasing the rates of eradication and lowering the prevalence and severity of the side effects. [ABSTRACT FROM AUTHOR]

With the rapid development of industry, environmental pollution is becoming more and more serious. The use of photocatalysts to degrade the pollutants could alleviate this problem. The perovskite oxides have been regarded as promising catalysts because of their excellent catalytic properties. In this study, the nanostructured perovskite Sr2Bi4Ti5O18 is prepared via a hydrothermal method and employed as a photocatalyst to degrade organic pollutants. The hydrothermal temperature is found to have a significant effect on the photocatalytic activity of Sr2Bi4Ti5O18, with the sample prepared at 180 °C exhibiting the highest degradation rate of Rh B (99% within 180 min), compared to those prepared at 140 °C (57% degradation rate) and 220 °C (90% degradation rate). The use of appropriate hydrothermal temperature benefits the increase in specific surface area and carrier transport rate of Sr2Bi4Ti5O18. The superoxide radicals (·O2−) and the holes (h+) were confirmed as the main active substances by the free radical capture experiments. This work develops a new layered perovskite photocatalyst Sr2Bi4Ti5O18 for environmental application. [ABSTRACT FROM AUTHOR]

Dopant impurity species can be incorporated into the silicon (001) surface via the adsorption and dissociation of simple precursor molecules. Examples include phosphine (PH3), arsine (AsH3), and diborane (B2H6) for the incorporation of phosphorus, arsenic, and boron, respectively. Through exploitation of precursor surface chemistry, the spatial locations of these incorporated dopants can be controlled at the atomic scale via the patterning of a hydrogen lithographic resist layer using scanning tunneling microscopy (STM). There is strong interest in the spatial control of bismuth atoms incorporated into silicon for quantum technological applications; however, there is currently no known precursor for the incorporation of bismuth that is compatible with this STM-based lithographic method. Here, we explore the precursor chemistry (adsorption, diffusion, and dissociation) of bismuth trichloride (BiCl3) on Si(001). We show atomic-resolution STM images of BiCl3 exposed Si(001) surfaces at low coverage and combine this with density functional theory calculations to produce a model of the surface processes and the observed features. Our results show that, at room temperature, BiCl3 completely dissociates to produce bismuth ad-atoms, ad-dimers, and surface-bound chlorine, and we explain how BiCl3 is a strong candidate for a bismuth precursor compound compatible with lithographic patterning at the sub-nanometer scale. [ABSTRACT FROM AUTHOR]

Bi 2 WO 6 is one of the promising triplet bismuth compound that has a layered structure with a high photocatalytic activity for photo-electrochemical (PEC) water splitting systems. Here, Bi 2 WO 6 synthesizes by the sonoelectrochemical method in pulse mode of ultrasound. Unexpectedly, synthetic samples show photocathode rather than photoanode activity in PEC systems. Applying of this method creates a leaf-like morphology with exposed [001] crystal facet and controllable amount of surface defects. The co-existence of oxygen and metal vacancies play a significant role in suppressing charge recombination and enhancing charge transporting in photoelectrodes. The creation of high surface vacancies leads to change the conduction and valence band positions and cause hydrogen evolution by Bi 2 WO 6 photoelectrodes. Another surprising result for the synthesized film by pulse mode is the creation of high photovoltage about 1.25 V that has a remarkable effect in suppressing charge recombination rate and proposed driving force for water reduction. Furthermore, the onset potential of the photoelectrodes improves and records high efficiencies (ABPE = 2.46% at −0.8 V and IPCE≈28% at 450 nm). The obtaining results introduces the sonoelectrochemical method as a promising method for the synthesis of highly efficient photoelectrodes. [Display omitted] • Bismuth tungstate films with a leaf like morphology formed by pulsed sonoelectrodepostion. • Simultaneous preferred growth of crystal facet {001} and creation of O and W vacancies. • Photoelectrode in PEC water splitting produces a high photovoltage (1.25 V). • Photoelectrode reduces the water molecules with ABPE = 2.46% at −0.8 V (vs. Ag/AgCl). [ABSTRACT FROM AUTHOR]

This paper provides a detailed evaluation of the photo-piezo-catalytic properties of lead-free Ba 0.85 Ca 0.15 Zr 0.1 (Ti 1-x Co x) 0.9 (BCZT- x Co, x = 0–0.025) ferroelectric ceramics prepared by a solid-state process. By control of the Co doping level, the band gap was reduced to 2.40 eV at the composition x = 0.02, which improved the generation of photo-generated charges and enhanced the photocatalytic activity. When a solution containing BCZT-0.02Co particles was subjected to both ultrasound and illumination, the degree of degradation of Rhodamine B reached 99% within 60 min, which was grater than when subjected to illumination or ultrasound alone. Examination of the dielectric properties, photoelectrochemical measurements and band energy structure of the materials provided new insights into the catalytic mechanism, where a strong coupling between piezoelectricity and photoexcitation was clearly observed. This work therefore highlights the attractive photo-piezo-catalytic properties of BCZT- x Co doped ceramics and is the first demonstration that Co substitution in these lead-free ferroelectric ceramics provides significant potential for photo-piezo-catalysis applications. [ABSTRACT FROM AUTHOR]

Herein, we report a twisted cubic Cu(I)4Ti(IV)4-oxo cluster stabilized by in situ – formed 2,2′-biphenolate ligands from the oxidative coupling of phenols. The 2,2′-biphenolate-functionalized Cu(I)4Ti(IV)4O4 cluster shows short Cu⋯C contacts and exhibits smaller HOMO–LUMO gaps than those of reported Ti(IV)4O4. [ABSTRACT FROM AUTHOR]

Lithium-sulfur (Li–S) batteries have been paid more attention due to its high theoretical specific capacity (1675 mAh g−1), but they still face many challenges in the commercialization process, especially the shuttle effect. Hence, reducing the shuttle of polysulfides is a key factor to obtain high-performance Li–S batteries. Inhere, bismuth based compounds were prepared as the sulfur host cathodes for Li–S batteries. Then the S@Co/N-CNTs@Bi2S3 and S@Co/N-CNTs@Bi2O3 composite cathodes were synthesized by alcohol heating and melt diffusion method. The as-prepared cathodes deliver a capacity decay rate of 0.038% and 0.056% during 900 cycles at 1 C, respectively. The outstanding cycling performance can be put down to the strong adsorption of Bi2S3 and Bi2O3 to polysulfides, inhibiting their dissolution and diffusion. The research proposed in this study will provide a new clue for bismuth based compounds as sulfur hosts to improve the cycle life of cathodes, and furnish a promising design strategy for the high-performance Li–S batteries. [ABSTRACT FROM AUTHOR]

Photothermal CO2 reduction with H2O, integrating advantages of photocatalysis driven H2O splitting and thermal catalysis promoted CO2 reduction, has drawn sharply increasing attention in artificial synthesis of solar fuels. The photothermal effect of metal nanoparticles facilities CO2 hydrogenation and activation of lattice oxygen in oxide photocatalyst promotes H2O oxidation, which is essentially considered for highly efficient photothermal catalysis. However, the large thermal conductivity of most metal nanoparticles induces inevitable heat dissipation, restricting the increase of catalyst temperature. In this work, to minimize the heat dissipation, we employ bismuth nanoparticles as photothermal unit, which is of the lowest thermal conductivity in the metal family. Meanwhile, we adopt bismuth doped NaTaO3 as photocatalytic unit because of the bismuth doping induced activation of lattice oxygen. The bismuth nanoparticles are assembled with bismuth doped NaTaO3 through one-step tunable transformation from Bi4TaO8Cl. Benefiting from the photothermal effect, thermal insulation caused by bismuth metal, and lattice oxygen activation by bismuth doping, the NaTaO3:Bi hybrid exhibits high photothermal catalytic performance. The yield of CO over NaTaO3:Bi hybrid at 413 K via photothermal catalysis is 141 times higher than that room temperature photocatalysis. Further, ultraviolet (UV) light irradiation leads to 89.2% selectivity of CO and visible light irradiation leads to 97.5% selectivity of CH4. This work may broaden the photocatalytic application of ABO3 perovskite and provides a novel strategy for the development of photothermal catalysts for artificial photosynthesis. [ABSTRACT FROM AUTHOR]

The oxidative addition of CF3SO3CH2Si(CH3)3 (NpSiOTf) toward organopnictogen(I) N,C,N-pincer compounds, i.e. [2,6-(DippN＝CH)2C6H3]E (1-E, where E = Sb, Bi; Dipp = 2,6-iPr2C6H3) produced compounds [2,6-(DippN＝CH)2C6H3]E(NpSi)(OTf) (2-E, where E = Sb, Bi). By analogy, the in situ reduction of [2,6-(Me2NCH2)2C6H3]ECl2 (3-E, where E = Sb, Bi) followed by treatment with NpSiOTf or MeI gave compounds [2,6-(Me2NCH2)2C6H3]E(R)(X) (R/X = NpSi/OTf 4-E, where E = Sb, Bi; R/X = Me/I 5-Sb). The reactivity of these compounds toward 1 eq. of K[BEt3H] was examined showing remarkable differences depending both on the ligand backbone and the pnictogen used. Thus in the case of 2-E, the addition of the hydride across the imino-function was achieved thereby yielding azapnicta-heterocyclic compounds [2-(DippNCH2)-6-(DippN＝CH)C6H3]E(NpSi) (6-E, where E = Sb, Bi). The same reaction of 4-Bi produced dibismuthine {[2,6-(Me2NCH2)2C6H3]Bi(NpSi)}2 (7-Bi), but in the case of 4/5-Sb the analogous distibines {[2,6-(Me2NCH2)2C6H3]Sb(R)}2 (R = NpSi7-Sb, Me 8-Sb) were not formed directly and hydrides [2,6-(Me2NCH2)2C6H3]Sb(R)H (R = NpSi9-Sb, Me 10-Sb) could be isolated instead. Nevertheless, heating of both 9-Sb and 10-Sb led to an activation of a labile Sb–H bond and the formation of distibines 7/8-Sb. [ABSTRACT FROM AUTHOR]

The effective separation and migration of photogenerated charge carriers in bulk and on the surface of photocatalysts will significantly promote photocatalytic efficiency. However, the synchronous regulation of photocharges on both counts is challenging. Herein, the simultaneous separation of bulk and surface photocharges is conducted to enhance photocatalytic activity by coupling the surface defects and lattice engineering of bismuth oxybromide. The depth-modulated Bi5O7Br ultrathin nanosheets with an abundance of bismuth in the crystal structure increased the internal electric field, which propelled the separation and migration of photocharges from bulk to the surface. Creation of oxygen vacancies (OVs) on the nanosheet surface forms local electric fields, which can stimulate the migration of charges to active sites on the catalyst surface. Therefore, the OV-assembled Bi5O7Br nanosheets demonstrated enhanced photocatalytic degradation efficiency under simulated solar-light illumination. This study proved the possibility of charge governing via electric field modulation based on an integrated strategy. [ABSTRACT FROM AUTHOR]

Nitrate, a common pollutant in water, can be used as a nitrogen source for electrocatalytic ammonia production. Bismuth oxide (Bi2O3) is a promising electrocatalyst because of earth‐abundance and high hydrogen overpotential. However, it also has the disadvantages of easy agglomeration and poor charge transfer. This study demonstrated that the high dispersion of Bi2O3 nanosheets can be achieved through in‐situ growth on Ti3C2Tx MXene nanosheets that improved the efficiency of charge transmission, and thus improving the electrocatalytic ammonia production performance. A NH3 yield rate of ∼7.00 mg h−1 cm−2 with faradic efficiency of 91.1 % could be achieved on 11 % Bi2O3/MXene. Density functional theory (DFT) calculations, electrochemical active surface area (ECSA) and electrochemical impedance spectroscopy (EIS) proved that the excellent ammonia production performance came from the fact that bismuth oxide itself could inhibit hydrogen evolution, and in situ growth on MXene enabled high active site exposure and enhanced charge transfer capacity. [ABSTRACT FROM AUTHOR]

Bismuth compounds have been playing an important role in thermoelectric (TE) applications. To match the high figure of merit (ZT) of n-type Bi-based TE materials for constructing effective TE devices, searching for p-type Bi-based TE materials with high ZT is highly desirable. Inspired by the successful exfoliation of BiOBr atomic layers [Wu et al., Angew. Chem. 130(28), 8855 (2018)], we systematically study the TE properties of single-layer BiOBr by using density functional theory and semiclassical Boltzmann transport theory, and we find that the p-type doped single-layer BiOBr exhibits a peak ZT value of 1.84 at 800 K, exceeding the highest value ever achieved among bulk p-type Bi-based TE materials (ZT = 1.4) [Poudel et al., Science 320(5876), 634 (2008)]. [ABSTRACT FROM AUTHOR]

The magnetoelectric response of the bismuth-deficient BiFeO3-BaTiO3 ceramics fabricated using a conventional solid-state reaction method was investigated. We found that a ferromagnetic BaFe12O19 phase is produced as a consequence of bismuth-deficiency (Bi-deficiency) and that the ceramics are 0–3 composites of BaFe12O19 and BiFeO3-based perovskite. An enhanced magnetoelectric response can be achieved in Bi-deficient composites as a consequence of the coupling between magnetostriction in the BaFe12O19 phase and the piezoelectric effect in the BiFeO3-based perovskite phase. In comparison with the composite ceramics prepared using a direct mixing method for the two components, Bi-deficient ceramics have a more uniform distribution of the BaFe12O19 phase in the perovskite matrix and a reduction in dielectric loss and conduction. Thus, the magnetoelectric response of Bi-deficient ceramics is greater than that of ceramics fabricated using a direct mixing method. Our work presents a simple approach for the fabrication of BiFeO3-based composite ceramics with uniformly distributed ferromagnetic particles and enhanced ferromagnetic and magnetoelectric responses. [ABSTRACT FROM AUTHOR]

Spectroscopic techniques, including photoelectron spectroscopy, diffuse reflectance, and x-ray absorption, are used to investigate the electronic structure and the local structure of LaOBiS 2 − x Se x thermoelectric material. It is found that Se substitution effectively suppresses local distortion that can be responsible for the increased carrier mobility together with a change in the electronic structure. The results suggest a possible way to control thermoelectric properties by tuning of the local crystal structure of these materials. [ABSTRACT FROM AUTHOR]

We studied the light-induced effects in BiFeO 3 single crystals as a function of temperature by means of optical spectroscopy. Here, we report the observation of several light-induced absorption features, which are discussed in terms of the photostriction effect and are interpreted in terms of excitons. The temperature dependence of their energy position suggests a possible coupling between the excitons and the lattice vibrations. Moreover, there are hints for anomalies in the temperature evolution of the excitonic features, which might be related to the temperature-induced magnetic phase transitions in BiFeO 3. Our findings suggest a coupling between light-induced excitons and the lattice and spin degrees of freedom, which might be relevant for the observed ultrafast photostriction effect in multiferroic BiFeO 3. [ABSTRACT FROM AUTHOR]

Interfacial reactions and underlying atomic mechanisms between Ta contacts (space group I m 3 ¯ m) and thermoelectric Bi2Te3 (space group R 3 ¯ m) are studied experimentally and theoretically. A Ta/Bi2Te3 mixture is found to be inert up to the melting point of Bi2Te3 (∼589 °C) based on calorimetry and interfacial composition analyses. This can be understood using density functional theory. Bi and Te adatoms hop across a close-packed Ta(110) surface in the <111>, <110>, and <100> directions with the highest dwelling time on equilibrium (fourfold hollow) sites, but they do not exchange with Ta surface atoms. To identify the electronic structure fingerprint of Ta(110) inertness, the adsorption energies and electron density distributions are calculated for the Bi2Te3 constituting atoms and possible dopants (15 elements) stemming from C, N, and O groups. C, N, O, and S strongly adsorb to Ta(110), exhibiting enhanced reactivity. We propose that these four species can initiate exchange diffusion with Ta due to ionic interactions between Ta and the adsorbates. Our results imply that elements with a high electronegativity should be avoided in Bi2Te3 doping because interfacial interactions may occur, degrading its stability and transport properties. [ABSTRACT FROM AUTHOR]

Interfacial reactions and underlying atomic mechanisms between Ta contacts (space group I m 3 ¯ m) and thermoelectric Bi2Te3 (space group R 3 ¯ m) are studied experimentally and theoretically. A Ta/Bi2Te3 mixture is found to be inert up to the melting point of Bi2Te3 (∼589 °C) based on calorimetry and interfacial composition analyses. This can be understood using density functional theory. Bi and Te adatoms hop across a close-packed Ta(110) surface in the <111>, <110>, and <100> directions with the highest dwelling time on equilibrium (fourfold hollow) sites, but they do not exchange with Ta surface atoms. To identify the electronic structure fingerprint of Ta(110) inertness, the adsorption energies and electron density distributions are calculated for the Bi2Te3 constituting atoms and possible dopants (15 elements) stemming from C, N, and O groups. C, N, O, and S strongly adsorb to Ta(110), exhibiting enhanced reactivity. We propose that these four species can initiate exchange diffusion with Ta due to ionic interactions between Ta and the adsorbates. Our results imply that elements with a high electronegativity should be avoided in Bi2Te3 doping because interfacial interactions may occur, degrading its stability and transport properties. [ABSTRACT FROM AUTHOR]

Transport measurements data are presented on bismuth-rich BiFeO3 ceramic, synthesized by a solid state method. Conductivity isotherms were analyzed using Jonscher's empirical power-law frequency dependence. Monotonically increasing frequency-exponent n(T) over 413–593 K indicates a small polaron tunnelling mechanism for the charge transport. Distinct linear regimes observed in the Arrhenius σdc vs. T−1 plot suggest that two different charge-carriers/conductivity-relaxations prevail above and below ∼490 K. Twin Arrhenius regimes of ac-conductivity also exhibit a sharp "transition" at 510 K, from the pinned-dipole/hopping-anion dynamics to the free-dipole/oscillating-ions response at higher temperatures. Furthermore, a concurrent behavior-change of the locus traced out by the charge-hopping frequency ωh [with σ(ωh) = 2σdc] also designates 510 K as delineating two different transport characteristics in the adjacent temperature regimes. [ABSTRACT FROM AUTHOR]

The electrocaloric effect (ECE) in lead-free relaxor ferroelectrics has gained significant interest over the past decades. However, certain aspects of the ECE in relaxor ferroelectrics, such as Bi0.5Na0.5TiO3, remain poorly understood. In this work, we investigate the ECE by considering Bi0.5Na0.5TiO3-SrTiO3 (BNT-ST) as an example. The results show that, for BNT-0.25ST ceramics, the directly-measured ECE is optimal when the freezing temperature is tailored to be about room temperature. For this material, ΔT = 0.51 K under an electric field of 6 kV/mm and the ECE has excellent thermal stability (the instability η ≤ 20% in the range 30–120 °C). The addition of strontium increases the cubic-phase fraction, enhances the local random field, and changes the local structure, as clarified by in situ Raman spectroscopy and piezoelectric force morphology. In addition, we discuss in detail the correlation between the ECE and local structure. This work thus improves our understanding of the ECE in BNT-based materials for EC cooling technologies. [ABSTRACT FROM AUTHOR]

In order to tailor the multiferroic as well as dielectric properties, we have synthesized BiFeO3 (BFO) and Ni-doped BFO nanoparticles of composition BiFe1-xNixO3 (0 ≤ x ≤ 0.07) via the sol-gel method. The influence of Ni-doping at the Fe site of BiFeO3 on the structural, dielectric, and multiferroic properties was investigated via various characterization techniques such as Raman spectroscopy, vibrating sample magnetometer, polarization-electric field (P-E) loop tracer, and LCR meter. The Raman spectra reveal the rhombohedral distorted perovskite structure of the samples in the R3c space group. The frequency dependent dielectric measurements at room temperature show that the dielectric constant for the pristine sample is an order of magnitude lower than the 1% Ni-doped BFO sample. It is also evident that the ac conductivity increases with the increase in frequency as well as Ni content. Further, the universal dielectric response (UDR) phenomenon is responsible for the dielectric behavior of all the samples in the whole frequency range except for the BiFeO3 and BiFe0.97Ni0.03O3 samples. These samples exhibit deviation from UDR phenomenon at higher frequencies. The room temperature hysteresis (M-H) loops exhibit the saturation in magnetization at higher magnetic fields. The result demonstrates a significant influence on the saturation magnetization with the Ni doping in BFO, prompting the ferromagnetic nature of the samples. The saturation magnetization of the 7% Ni-doped sample is approximately six times higher than the pristine one. The saturated P-E hysteresis loops establish the ferroelectric nature of the synthesized samples that are enhanced significantly on Ni doping. Thus, the doping of Ni in BiFeO3 improves the multiferroic properties of the matrix. [ABSTRACT FROM AUTHOR]

To date the climate intervention (CI) proposal of cirrus cloud thinning (CCT) was only assessed in general circulation models (GCMs) using a globally uniform distribution of artificial ice nucleating particles (INPs). In this study, we made the first attempt using the ECHAM-HAM GCM to simulate CCT using a fully prognostic cirrus seeding aerosol species. Seeding particles were assumed to be made of bismuth-triiodide and were emitted into the atmosphere following aircraft emissions of black carbon (soot). This new approach drastically reduced the number concentration of seeding particles available as INPs in our cirrus ice nucleation sub-model compared to the globally uniform approach. As a result, we found that in order to achieve a significant signal we needed to reduce the assumed radius of emitted seeding particles by an order of magnitude to 0.01 μm and scale the mass emissions of seeding particles by at least a factor of 100 or 1000. This latter scaling factor led to a large net TOA warming effect of 5.9 Wm-2. This warming effect was a clear response to overseeding with a large concentration of seeding particles (> 105 L-1 in the northern hemisphere) that was most evident in the tropics. Due to this undesired effect, in a second series of simulations we avoided seeding the tropics by restricting emissions to only the northern hemisphere (NH) during winter. We also found a small and insignificant effect, or overseeding, which for the extreme case was reduced compared to the global aircraft emission scenario (2.2 Wm-2). Ice crystal radius anomalies were not what we expected, with the largest reduction in size found for the case with a mass scaling factor of 10 instead of the extreme, x1000, scenario. We attributed this peculiar behavior to the differences in the competition between different seeding particle concentrations and background particles. Finally, we also found that seeding with such large concentrations increased the albedo effect of mixed-phase clouds in the NH due to less efficient cloud droplet consumption, consistent with previous findings from our model. Overall, however, based on this study it is recommended to pause further modeling efforts of CCT unless more observational-based evidence of aerosol-ice-cloud interactions indicates favourable conditions for producing the desired outcome of this CI proposal. [ABSTRACT FROM AUTHOR]

Nanoporous BiVO4 thin films were deposited on fused silica substrate using reactive magnetron sputtering. The effect of annealing temperature on the microstructure, morphology and optical properties was evaluated. The samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), ultraviolet-visible spectroscopy (UV-Vis) and X-ray photoelectron spectroscopy (XPS). XPS demonstrated the Bi+3 and V+5 oxidation states, as well as the adsorbed and lattice oxygen on the film surface. The as-deposited films proved to be amorphous by the XRD results, while the pure monoclinic scheelite BiVO4 crystal structure was obtained after a post-annealing treatment at 300 and 450ºC. FESEM images displayed a uniform surface with no grain boundaries for the as-deposited film, whereas nanopores with an average diameter of 2040 nm were observable in the film annealed at 450ºC as opposed to the film annealed at 300 ºC with a dense and cracked surface. The association of nanoporosity with the efficiency of visible-light absorption was demonstrated by the UV-Vis spectrophotometry results with the narrowest bandgap (2.5 eV) concerning the film annealed at 450 ºC. The photocatalytic experiment under visible light showed an 80 % photodegradation of Rhodamine-B solution after 7 h, and the recycling experiment proved the stability of the thin films after three cycles. These results show the great potential of BiVO4 thin films deposited by reactive magnetron sputtering in photocatalytic wastewater treatment applications. [ABSTRACT FROM AUTHOR]